Greetings! Today, we're exploring Stacks, a crucial data structure in computer science. A stack
can be likened to a pile of plates: you add a plate to the top (Last In) and take it from the top (First Out). This Last-In, First-Out (LIFO) principle is fundamental to understanding stacks. This lesson will guide you through the stack data structure, its operations, and its applications. Let's get started!
To create a stack, we can use a MutableList
in Kotlin. For the Push operation, we use add()
, which inserts an element at the end of the list. For the Pop operation, there's the removeAt()
function that removes the last element, simulating the removal of the 'top' element in a stack. Here's how it looks:
In the example provided, we add 'John', 'Mary', and 'Steve' to the stack and then remove 'Steve' from it.
Stack operations go beyond merely add
and removeAt
. For example, to verify if a stack is empty, we can use the isEmpty()
method. If it returns , the stack is empty. Conversely, if it returns , the stack is not empty. To peek at the top element of the stack without popping it, we use indexing with .
